As a slide fastener for opening and closing left and right front parts of clothes, a slide fastener attached with a separable bottom end stop having a separable pin, a box pin, and a box in the lower ends of left and right element rows has been widely used.
In the slide fastener attached with a separable bottom end stop, in general, the separable pin is continuously disposed to the lower end of the one-side element row, and the box pin is continuously disposed to the lower end of the other-side element row. In addition, the slide fastener is configured so that the box for inserting the separable pin is fixedly disposed to the lower end portion of the box pin and so that the separable pin can be inserted into/detached from the box through a slider in the state where the slider is slid down to the lower end position contacting with the box.
Accordingly, in the slide fastener attached with a separable bottom end stop, after the separable pin is inserted into the box, the left and right element rows are coupled with each other by sliding the slider in the upward direction, that is, the element coupling direction. In addition, the left and right element rows that are coupled with each other are separated by sliding the slider toward the box in the downward direction, and after the slider contacts with the box, left and right fastener stringers are separated by detaching the separable pin from the box.
In addition, as a slide fastener for coupling and separating the left and right fastener stringers, a slide fastener where a reverse-opening lower slider is allowed to pass through the element rows instead of the aforementioned box is also well known. In the slide fastener, in general, two sliders, that is, the upper slider and the reverse-opening lower slider are allowed to pass through the element rows in the bottom-aligned state so as to allow the corresponding rear openings to face. In addition, the slide fastener is configured so that the separable pin can be inserted into/detached from the lower slider through the upper slider in the state where the upper and lower sliders are slid down to the lower end position where the box pin is disposed.
In addition, for example, Japanese Patent Application Laid-Open No. 2000-106917 (Patent Document 1) discloses a slide fastener which can be used as the upper-opening type or the two-side-opening type by selecting one of the box of the separable bottom end stop and the reverse-opening lower slider.
As illustrated in the case of using a box 78 in FIG. 15, a slide fastener 71 disclosed in Patent Document 1 includes fastener stringers 74 where coil-like fastener elements 73 are attached to facing side edge portions of a pair of left and right fastener tapes 72, a slider (not shown) which is allowed to pass through left and right element rows 75 constructed with the fastener elements 73, a separable pin 76 which is attached to an end portion of the one-side element row 75, a box pin 77 which is attached to an end portion of the other-side element row 75, and a box 78 which is fitted into the box pin 77.
The fastener stringer 74 includes a reinforcing portion 79 constructed with a thermoplastic resin film for reinforcing the end portion of the fastener tape 72. The end edge portion of the reinforcing portion 79 facing the tape is cut by a suitable size, and the thermoplastic-resin separable pin 76 or box pin 77 is disposed to the cut portion.
In addition, in the separable pin 76 and the box pin 77, thin guide portions 80 where the flanges of the slider can be freely slid are disposed to be adjacent to the separable pin 76 or the box pin 77. Rectangular parallelepiped-shaped reinforcing line portions 81 raised on the front and rear portions of the fastener tapes 72 are disposed to the sides of the guide portions 80. In addition, a stopper 82 whose height is smaller than that of the box pin 77 and larger than those of the reinforcing line portions 81 is formed from the front end of the box pin 77 to the front end of the reinforcing line portion 81 in a curved shape at the surface side of the guide portion 80. The guide portion 80, the reinforcing line portion 81, and the stopper 82 are formed to be integrated with the separable pin 76 or the box pin 77 by using a thermoplastic resin.
Furthermore, the separable pin 76 is formed so that the front end portion (the end portion opposite to the side of the element row 75) is slightly curved toward the inner side of the tape and so that the side wall of the reinforcing line portion 81 facing the separable pin 76 is cut out to be easily fitted into the box 78 or the reverse-opening slider. In addition, in the end portion of the separable pin 76 on the side of the element row 75, a protrusion 83 protrudes toward the box pin 77. When the left and right element rows 75 are coupled with each other, the protrusion 83 is coupled with the element 73 on the side of the box pin 77, so that the coupling strength in the end portion of the element row 75 is increased. On the other hand, a plurality of small protrusions 84 is erected on the side of the front end portion of the front surface (upper surface) of the box pin 77. By using the small protrusions 84, the later-described box 78 is fused and adhered to the box pin 77.
In the slide fastener 71 disclosed in Patent Document 1, in the case where the box 78 is fitted into the box pin 77, the outer appearance of the box 78 is formed in an approximately rectangular shape, and an insert groove (not shown) whose thickness is slightly smaller than that of the stopper 82 and which the portion where the guide portion 80 is formed can be inserted into is disposed in the box 78. In addition, the box 78 has a partitioning portion 85 in the central portion, and a box-pin-insertion hole 86 and a separable-pin-insertion hole 87 are disposed at the left and right portions thereof. In addition, an engaging hole (not shown) into which the stopper 82 is inserted to be engaged is disposed in the deepest portion of the box-pin-insertion hole 86.
The box 78 is inserted into the box pin 77, and the engaging hole provided in the deepest portion of the box-pin-insertion hole 86 is inserted into the stopper 82, so that the box 78 is fixed. After that, the small protrusions 84 formed to protrude on the box pin 77 is welded to the box 78 by performing an ultrasonic wave process from the surface side of the box 78, so that the separable bottom end stop of the slide fastener 71 is configured.
On the other hand, in Patent Document 1, in the case where the two-side-opening type slide fastener 71 is configured, the upper-opening upper slider and the reverse-opening lower slider may be allowed to pass through the fastener stringer 74 where the box pin 77 is formed. In this case, the same type slider can be used for the upper-opening slider and the reverse-opening slider.
In the case of the slide fastener 71 disclosed in Patent Document 1, the upper-opening type slide fastener 71 having one slider and the separable bottom end stop and the two-side-opening type slide fastener having a pair of sliders can be selectively manufactured at high efficiency without using a particular type slider, so that it is possible to stabilize and supply the slide fasteners in immediate response to the demands.
On the other hand, Taiwanese Patent No. 526718 (Patent Document 2) discloses a two-side-opening type slide fastener where a separable pin and a box pin which are injection-molded in a fastener stringer can be easily inserted into a slider and the slider is prevented from being detached from the separable pin and the box pin.
In the slide fastener disclosed in Patent Document 2, top stoppers are disposed in the one end of each of left and right element rows, and a separable pin and a box pin are disposed in the other end. In addition, a protrusion which protrudes toward the inner side of the tape from the side edge of the box pin on the side of the fastener tape is formed in the front end portion (the end portion opposite to the side of the element row) of the box pin.
In addition, fitting portions which can be fitted to each other are disposed to extend in the end portion of the separable pin on the side of the element row and the end portion of the box pin on the side of the element row, so that when the left and right element rows are coupled with each other, the separable pin and the box pin are prevented from being moved in the longitudinal direction of the element row. In addition, before the separable pin and the box pin are molded, the upper slider and the lower slider are allowed to pass through the element rows of the slide fastener in advance.
In the case of the slide fastener disclosed in Patent Document 2, the upper and lower sliders can be allowed to easily pass through the element rows before the separable pin and the box pin are molded, and the upper and lower sliders allowed to pass through the element rows are prevented from being detached from the element rows by the top stoppers disposed on the end portions of the element rows and the protrusion formed on the box pin.    Patent Document 1: Japanese Patent Application Laid-Open No. 2000-106917    Patent Document 2: Taiwanese Patent No. 526718